On Monday, Environment Canada issued the warning for High River, Okotoks, Claresholm, Lethbridge, Taber, Milk River, Cypress Hills, Foremost, Kananaskis, Canmore, Cardston, Fort Macleod, Magrath, Crowsnest Pass, Pincher Creek and Waterton.
Forecasters are predicting as much as 160 millimetres could fall in the Pincher Creek and Cardston areas.
However, in 2013 it took an accumulation of 345 millimetres of rain to trigger the flooding that devastated High River.
Nevertheless, the Wallaceville area of High River is now under a flood watch, with officials saying a 1.2 metre rise is possible and the forecast flows could approach flood thresholds. There is currently no flooding concerns for other locations in the community.
High streamflow advisories have been issued for streams and rivers in the Bow, Oldman, Milk and South Saskatchewan River basins.
Meteorologist David Spence said the system will move fairly quickly to the east by Tuesday.
“If not sooner, some of the heaviest rain is going to be pulling away from the Foothills and towards Saskatchewan and most if not all of it, the heavy stuff at least will be south of Calgary,” he said.
However, Spence said Wednesday's forecast could cause some concern in Calgary.
“It’s looking in excess of 20 millimetres of rain, so if we have the rain that we’re getting tonight (Monday) and tomorrow saturating the ground, and then the heavier rain getting in on Wednesday, that sets the stage for perhaps some minor flooding in Calgary,” Spence said.
A special ceremony is scheduled to take place on Friday in Calgary to commemorate the 2013 flood, in which 80,000 Calgarians were forced to flee their homes and the entire community of High River was evacuated.
Also on HuffPost